Solid State Light (SSL) sources such as, but not limited to, light emitting diodes (LEDs) will play an increasingly significant role in general lighting in the future. This will result in more and more new installations being equipped with LED light sources in various ways. The reason for replacing state of the art light sources with LED light sources is e.g. the lower power consumption of LED light sources and their extremely long lifetime.
Typically, an LED is driven by means of a special circuit, which is called the driver. In order to permit the operation of different kinds of LED light sources with a given driver to come to a more or less modular system, it is desirable that LED lamps are able to communicate their required supply power characteristics to the driver. This allows replacing the LED lamp with a newer version offering for example better efficiency or a wider color range without changing the driver. Further, this allows reducing the different types of drivers held in stock.
For example US 2004/0056774 A1 discloses a supply unit for at least one LED unit, wherein the supply unit has a detection unit designed for detecting the identity of the LED unit by means of electrical quantities. The identity of the LED unit is detected via the supply terminals of the supply unit, the supply terminals being adapted for supplying power to the LED unit.
However, this allows only for the detection of an identity of an LED unit, not a dynamic adaptation of the characteristics of the supplied power depending on the actual requirements of the LED lamp. In case an LED lamp is connected to an LED driver, the driver may thus only detect some fixed internal parameters of the lamp and set the power accordingly to these fixed parameters. This system lacks the ability to drive the lamp accordingly under different operation conditions of the lamp.